Object-related regularities are processed automatically: evidence from the visual mismatch negativity

Abstract

One of the most challenging tasks of our visual systems is to structure and integrate the enormous amount of incoming information into distinct coherent objects. It is an ongoing debate whether or not the formation of visual objects requires attention. Implicit behavioral measures suggest that object formation can occur for task-irrelevant and unattended visual stimuli. The present study investigated pre-attentive visual object formation by combining implicit behavioral measures and an electrophysiological indicator of pre-attentive visual irregularity detection, the visual mismatch negativity (vMMN) of the event-related potential. Our displays consisted of two symmetrically arranged, task-irrelevant ellipses, the objects. In addition, there were two discs of either high or low luminance presented on the objects, which served as targets. Participants had to indicate whether the targets were of the same or different luminance. In separate conditions, the targets either usually were enclosed in the same object or in two different objects (standards). Occasionally, the regular target-to-object assignment was changed (deviants). That is, standards and deviants were exclusively defined on the basis of the task-irrelevant target-to-object assignment but not on the basis of some feature regularity. Although participants did not notice the regularity nor the occurrence of the deviation in the sequences, task-irrelevant deviations resulted in increased reaction times. Moreover, compared with physically identical standard displays deviating target-to-object assignments elicited a negative potential in the 246-280 ms time window over posterio-temporal electrode positions which was identified as vMMN. With variable resolution electromagnetic tomography (VARETA) object-related vMMN was localized to the inferior temporal gyrus. Our results support the notion that the visual system automatically structures even task-irrelevant aspects of the incoming information into objects.

Prediction errors in surface segmentation are reflected in the visual mismatch negativity, independently of task and surface features

“…The P2-N2 effect found here closely mirrors that seen in an earlier study of regularity violation in objectto-object relations (Müller et al, 2013). In that study, participants responded to a pair of targets that were situated within-or across-objects.…”

“…More recently, researchers conducted an investigation of how mismatch effects would be driven by changes in irrelevant object relations (Müller, Widmann, & Schröger, 2013). There, participants saw a stream in which each presentation featured two ellipsoid ''objects'' and two separate targets that were to be compared.…”

Visual mismatch negativity: a predictive coding view

“…Recent studies demonstrated that object-based irregularities are automatically detected by the visual system (Müller et al, 2013), as well as irregular lexical information (Shtyrov et al, 2013). Another recent study showed that visual mismatch negativity (vMMN) can be elicited both by real and illusory brightness changes (Sulykos and Czigler, 2014).…”

Visual Mismatch Negativity (vMMN): a Prediction Error Signal in the Visual Modality

“…Sufficiently large magnitude of change thus elicited typical oblique effect as indexed by vMMN. Müller et al (2013) used vMMN to study whether object formation happens in the absence of attention. Using an elegant design, participants were presented with two symmetrically arranged ellipses, and two discs of either lower or higher luminance.…”